VMware said its security team became aware of the public posting of a single file from the ESX source code, as well as the possibility that more files may be posted in the future, on Monday. The company revealed that the posted code and associated commentary dates to the 2003 to 2004 time frame.

Iain Mulholland, director of the VMware Security Response Center, was quick to say that just because source code may have been publicly shared does not necessarily mean that there is any increased risk to VMware customers.

"VMware proactively shares its source code and interfaces with other industry participants to enable the broad virtualization ecosystem today," Mulholland wrote in a VMware blog post. "We take customer security seriously and have engaged internal and external resources, including our VMware Security Response Center, to thoroughly investigate."

Virtual Infrastructure: A Prime Target

Mulholland said VMware will continue to provide updates to the VMware community if and when additional information is available. That was on Tuesday. VMware has not yet offered any new information.

We caught up with Eric Chiu, president of HyTrust, a cloud and virtual infrastructure control company, to get his views on VMware's security issue. He started out by telling us that virtualization is mainstream, with more than 50 percent of enterprise data centers now virtualized.

"Because of this success, virtual infrastructure is a prime target for attack -- so the theft of VMware ESX source code, similar to RSA's breach last year, is no surprise," Chiu said. "Platform security for virtual infrastructure is a must -- without securing the virtual infrastructure, enterprises are leaving a huge area of their data center open to attack."

No One Is Immune

We also touched base with Mark Bower, data protection expert and vice president at Voltage Security, a data-centric security and simplified key management firm. He told us that although the details are sketchy, the attack once again shows that even the best-prepared companies can have risks from consequential third-party access to data out of their control.

"The real pain for the industry in this case is less about counterfeit VMware instances, but the intimate knowledge attackers may now possess of possible vulnerabilities in a critical virtualization tool that is the foundation for many enterprise data centers, clouds and applications," Bower said.

"Nobody should be assuming that security by obscurity is the way to protect critical data -- that's been the case since the 1800s. This incident again underpins the industry's critical and growing need to adopt a data-centric security approach -- so irrespective of where data may reside, even in vulnerable systems it stays protected until the moment it's needed. And in the attackers' hands, it's useless -- even if they know exactly how the container the data is in functions and can itself be compromised."

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